From mboxrd@z Thu Jan 1 00:00:00 1970 From: Herbert Xu Subject: Re: [Patch net] bridge: do not expire mdb entry when bridge still uses it Date: Fri, 8 Mar 2013 10:31:51 +0800 Message-ID: <20130308023151.GA27155@gondor.apana.org.au> References: <1362708423-23932-1-git-send-email-amwang@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: netdev@vger.kernel.org, bridge@lists.linux-foundation.org, Stephen Hemminger , "David S. Miller" , Adam Baker To: Cong Wang Return-path: Received: from sting.hengli.com.au ([178.18.18.71]:60075 "EHLO fornost.hengli.com.au" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1759432Ab3CHCcQ (ORCPT ); Thu, 7 Mar 2013 21:32:16 -0500 Content-Disposition: inline In-Reply-To: <1362708423-23932-1-git-send-email-amwang@redhat.com> Sender: netdev-owner@vger.kernel.org List-ID: On Fri, Mar 08, 2013 at 10:07:03AM +0800, Cong Wang wrote: > From: Cong Wang > > This is a long-standing bug and reported several times: > https://bugzilla.redhat.com/show_bug.cgi?id=880035 > http://marc.info/?l=linux-netdev&m=136164389416341&w=2 > > This bug can be observed in virt environment, when a KVM guest > communicates with the host via multicast. After some time (should > be 260 sec, I didn't measure), the multicast traffic suddenly > terminates. > > This is due to the mdb entry for bridge itself expires automatically, > it should not expire as long as the bridge still generates multicast > traffic. It should expire when the bridge leaves the multicast group, > OR when there is no multicast traffic on this bridge. > > I fix this by adding another bool which is set when there is > multicast traffic goes to the bridge, cleared in the expire timer and > when IGMP leave is received. I ran omping for 15 minutes, everything > looks good now. I gather from the bugzilla entry that this happens where there is no querier in the network. So my question is why does this only affect the bridge port and not other ports on the bridge? Cheers, -- Email: Herbert Xu Home Page: http://gondor.apana.org.au/~herbert/ PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Date: Fri, 8 Mar 2013 10:31:51 +0800 From: Herbert Xu Message-ID: <20130308023151.GA27155@gondor.apana.org.au> References: <1362708423-23932-1-git-send-email-amwang@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1362708423-23932-1-git-send-email-amwang@redhat.com> Subject: Re: [Bridge] [Patch net] bridge: do not expire mdb entry when bridge still uses it List-Id: Linux Ethernet Bridging List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Cong Wang Cc: Stephen Hemminger , netdev@vger.kernel.org, bridge@lists.linux-foundation.org, "David S. Miller" , Adam Baker On Fri, Mar 08, 2013 at 10:07:03AM +0800, Cong Wang wrote: > From: Cong Wang > > This is a long-standing bug and reported several times: > https://bugzilla.redhat.com/show_bug.cgi?id=880035 > http://marc.info/?l=linux-netdev&m=136164389416341&w=2 > > This bug can be observed in virt environment, when a KVM guest > communicates with the host via multicast. After some time (should > be 260 sec, I didn't measure), the multicast traffic suddenly > terminates. > > This is due to the mdb entry for bridge itself expires automatically, > it should not expire as long as the bridge still generates multicast > traffic. It should expire when the bridge leaves the multicast group, > OR when there is no multicast traffic on this bridge. > > I fix this by adding another bool which is set when there is > multicast traffic goes to the bridge, cleared in the expire timer and > when IGMP leave is received. I ran omping for 15 minutes, everything > looks good now. I gather from the bugzilla entry that this happens where there is no querier in the network. So my question is why does this only affect the bridge port and not other ports on the bridge? Cheers, -- Email: Herbert Xu Home Page: http://gondor.apana.org.au/~herbert/ PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt